The present invention relates to target cell-specific non-viral vectors, to pharmaceutical compositions that comprise such vectors, and to the use of these vectors in gene therapy.
The aim of gene e therapy is to insert a foreign gene(s) into the cell s of an organism in order either to switch off defective genes, to replace a defective gene with an intact gene, or to enable these cells to form a protein that possesses a prophylactic or therapeutic effect.
Vectors for insertion of genes into eukaryotic cells, b based on viruses , are well known in the art. Viruses have developed a differentiated system by means of which they bind specifically to cells by means of coat proteins, and, after being endocytosed via endosomes, are able to penetrate the membrane of these endosomes and reach the interior of the host cells. Viruses have therefore been used as carriers for inserting foreign genes into the cell. This technology, in its different variations, and the viruses that are used for this purpose, have already been described in detail (see the reviews of Hodgson, Bio/Technology, 3: 222 (1995); and Jolly, Cancer Gene Therapy, 1: 51 (1994)).
The principle underlying this technology is that parts of the viral gene are replaced by the desired foreign gene so that a viral vector is produced. As a rule, viral vectors are no longer able to replicate, due to the manipulation. However, all the genes that encode the viral coat proteins and regulate the expression of these viral genes must be present to enable these viral vectors to replicate.
It has been found, however, that viral vectors can give rise to problems, particularly when being used in humans. There is the danger of recombination with wild-type viruses of the same species, as a result of which pathogenic viruses might be produced. Furthermore, viral coat proteins can trigger immune reactions in the recipient. As viral vectors take the same route of infection in the cell as do the corresponding wild viruses, there is the danger of the host genes being mutated as a result of the foreign genes being integrated into the host chromosomes (activation of quiescent genes, destruction of active genes).
A further disadvantage of viral vectors is that the geometry of the viruses restricts their ability to accommodate many foreign genes.
In view of these limitations and dangers of viral vectors, attempts have been made to find virus-independent methods of inserting genes into cells. The principle underlying one of these methods is fusing the negatively charged cell membrane with the negatively charged gene so that the gene is taken up by the cell, and penetrates into the cytoplasm through the endosomal membrane or the lysosomal membrane. Apart from developing physical (enclosure of gene particles, osmotic, thermal or electrical alterations to the cell membrane) or chemical (organic solvents, detergents, enzymes) methods for altering the cell membrane, gene carriers have been developed that mediate fusion of the genes with the cell membrane. These carriers include liposomes, cationic polypeptides, dendrimeric polymers or cationic amphiphilic substances (for reviews, see Behr, Bioconjugate Chem., 5: 382 (1994); Afione et al., Clin. Pharmakokinet., 28: 181 (1995) and Felgner, Adv. Drug Delivery Rev., 5: 163 (1990)).
Synthetic cationic amphiphilic substances, such as dioleoyloxypropyltrimethylammonium bromide (DOTMA) in a mixture with dioleoylphosphatidylethanolamine (DOPE) or lipopolyamine (see Behr above), have gained considerable importance in this type of charged gene transfer. The mechanism of action of these cationic amphiphilic substances or substance mixtures is that, due to an excess of cationic charge, they both complex with the negatively charged genes and bind to the anionic cell surface. The amphiphilic character of these carriers leads to fusion with the cell membrane. However, the transfection rate which can be achieved is still markedly less than when using viral vectors. Furthermore, the excess cationic charge on the complexes composed of non-viral carriers and DNA is neutralized, after in-vivo administration, by anionic biological substances (proteins, heparins, etc.), thereby impairing binding to cells.
It, therefore, is an object of this invention to provide a means for inserting a foreign gene into a eukaryotic cell that avoids the drawbacks of prior art methods. This and related objects have been achieved by the invention described below.
The present invention is based in part on the concept that cells can take up genes through the process of endocytosis. The endocytosis process is normally followed by enzymic degradation of the foreign genes in the endosomes or lysosomes. Only those genes that can evade this enzymic degradation and can penetrate through the membrane of the endosomes/lysosomes into the cytoplasm and/or into the cell nucleus are able to be expressed by transcription. In the case of the novel target cell-specific vectors described herein, the local concentration of the vectors at the target cell is increased in vivo as the novel vectors are provided with target cell-specific ligands.
The present invention relates, therefore, to target cell-specific non-viral vectors for inserting at least one gene into cells of an organism, which vectors comprise the following components:
(a) a non-viral carrier for the gene to be inserted,
(b) a ligand which can bind specifically to the desired target cell,
(c) a fusion protein for the penetration of the vector into the cytoplasm of the target cell, and
(d) the gene to be introduced.
In the novel vectors, the individual components of the target cell-specific vector are bonded to each other covalently and/or by means of adsorptive bonding. The present invention also relates to a pharmaceutical composition comprising the above vector.
The non-viral carrier (a) (see description above) for the gene, that is used in accordance with the invention, is preferably a protein, polypeptide, polysaccharide, phospholipid, cationic lipid, glycoprotein, lipoprotein or lipopolyamine that can be cationized by introducing positively charged side groups, with the bonding between the non-viral carrier and a positively charged side chain being effected by adsorptive or covalent bonding. Furthermore, the carrier can be given amphiphilic properties by an additional adsorptive or covalent bonding-on of lipophilic side groups. In a particularly preferred embodiment, the non-viral carrier (a) is albumin or xylan.
The ligand (b) that is employed in accordance with the invention is selected on the basis of specific binding to the outer membrane of a particular animal or human cell. For binding specifically to endothelial cells, ligand (b) is preferably selected from the group consisting of a monoclonal antibody, or a fragment specific for endothelial cells, a glycoprotein that carries mannose terminally, glycolipid, polysaccharide, cytokine, growth factor, adhesion molecules and glycoproteins from the coats of viruses that possess a tropism for endothelial cells. The last-named is a particularly preferred embodiment.
In another preferred embodiment, ligand (b) that binds specifically to smooth muscle cells is selected from the group consisting of a monoclonal antibody, or its fragments thereof, that specifically bind to actin, cell membrane receptor, a growth factor, and a glycoprotein from the coats of viruses that possesses tropism for smooth muscle cells. The last-named is a particularly preferred embodiment.
In a further preferred embodiment, a ligand (b) that binds specifically to macrophages and/or lymphocytes is selected from the group consisting of a monoclonal antibody that is specific for a membrane antigen on macrophages or lymphocytes, an intact immunoglobulin or Fc fragments of polyclonal or monoclonal antibodies that are specific for membrane antigens on macrophages and lymphocytes, cytokine, growth factor, a peptide carrying mannose terminally, protein, lipid, polysaccharide and glycoprotein from the coat of virus, in particular the HEF protein of influenza C virus having a mutation in nucleotide position 872, or HEF cleavage products of influenza C virus which contain the catalytic triad serine-71, histidine 368 or 369 and aspartic acid 261. The last named is the particularly preferred embodiment.
Ligand (b) that binds specifically to glial cells is selected from the group consisting of an antibody or antibody fragment thereof that binds specifically to membrane structures of glial cells, an adhesion molecule, a peptide carrying mannose terminally, a protein, a lipid or a polysaccharide, growth factor, and a glycoprotein from the coat of a virus that possesses a tropism for glial cells. The last named is particularly preferred.
In a further preferred embodiment, ligand (b) binds specifically to hematopoietic cells, and is selected from the group consisting of an antibody or antibody fragment that is specific for a stem cell factor, IL-1 (in particular receptor type I or II), IL-3 (in particular receptor type xcex1 or xcex2), IL-6 or GM-CSF receptor, an intact immunoglobulin or Fc fragment thereof that exhibits this specificity, growth factor such as SCF, IL-1, IL-3, IL-6 and GM-CSF, and Hepatocyte Growth Factor and a fragment thereof that binds to the corresponding receptor.
In yet another preferred embodiment, ligand (b) can bind specifically to leukemia cells and is selected from the group consisting of an antibody or antibody fragment thereof, an immunoglobulin or Fc fragment that bind specifically to membrane structures on leukemia cells such as CD13, CD14, CD15, CD33, CAMAL, sialosyl-Le, CD5, CD1e, CD23, M38, IL-2 receptors, T-cell receptors, CALLA or CD19, and also growth factors, or fragments that derive from them, and retinoids.
A ligand (b) that can bind specifically to virus-infected cells is preferably selected from the group consisting of an antibody or antibody fragment thereof, and an intact immunoglobulin or Fc fragment that is specific for a viral antigen which, after infection with the virus, is expressed on the cell membrane of the infected cell.
Finally, ligand (b) can also be a ligand that binds specifically to bronchial epithelial cells, and sinusoidal cells of the liver or hepatocytes, and is selected from the group consisting of transferring, an asialoglycoprotein such as asialoorosomucoid, a neoglycoprotein, galactose, insulin, a peptide carrying mannose terminally, protein, lipid, polysaccharide, intact immunoglobulin or Fc fragment which bind specifically to the target cells, and glycoproteins from the coats of viruses that bind specifically to the target cells. The last-named embodiment is particularly preferred.
A fusion protein (c) is selected from the group consisting of hemagglutinin of influenza A or A viruses, the HA2 component of the hemagglutinin of influenza A or B viruses, a peptide analogue thereof, the M2 protein of influenza A viruses, the HEF protein of influenza C viruses, a transmembrane protein of filoviruses, a transmembrane glycoprotein of rabies virus, vesicular stomatitis virus, Semliki Forest Virus, tickborn encephalitis virus, a fusion protein of HIV virus, Sendai virus, respiratory syncytial virus, and a fragment of said viral fusion proteins or of transmembrane glycoprotein from which the transmembrane region was removed.
In a preferred embodiment, a fusion protein (c) is selected from the group consisting of hemagglutinin or influenza A or B viruses, the HA2 component of the hemagglutinin or influenza A or B viruses and peptide analogs thereof, the M2 protein of influenza A viruses, the HEF protein of influenza C viruses, a transmembrane protein of filoviruses such as Marburg virus or Ebola virus, a transmembrane glycoprotein of rabies virus, vesicular stomatitis virus, Semliki Forest virus, tickborn encephalitis virus, a fusion protein of HIV virus, Sendai virus (in particular the F1 component) or respiratory syncytial virus (in particular the gp37 component) and fragments of these viral fusion proteins or of the transmembrane glycoproteins that contain the fusiogenic peptides.
In a preferred embodiment, the gene (d) which is to be introduced is in the form of a plasmid.
The novel vectors can be employed as a pharmaceutical or a constituent of a pharmaceutical, with the vectors preferably being used for preparing a pharmaceutical for the intravenous, intraarterial, intraportal, intracranial, intrapleural, intraperitoneal or local introduction of a desired gene into specific target cells. Pharmaceutically acceptable carriers for the novel vectors are those listed in Remington""s Pharmaceutical Sciences, Mack Publishing Co., Easton, Pa. 1988, hereby incorporated by reference.
Use of the novel target cell-specific vectors ensures that, after the vector has been administered parenterally, preferably intravenously or intraarterially, its concentration at the target cell can be raised and the rate at which the target cell is transfected can consequently be increased. This advantage in accordance with the invention is achieved by a synergistic effect of the individual, mutually linked components of the novel vectors.
The target cell-specific ligand (b) should exhibit a high specificity for the desired target cells. In a preferred embodiment, ligand is a viral coat protein which is specific for particular cells. A suitable viral coat protein is selected on the basis of the desired target cell. As these target cell-specific ligands, in particular the viral coat proteins, are coupled to the carrier for the desired gene, the desired gene binds to the target cell by way of the target cell-specific ligand and becomes enriched at the target cell.
The non-viral carriers (a) for the gene are preferably those compounds that are known to have a long half-life in the blood. As a result of this relatively long half-life in the blood, the target cell is exposed for as long as possible to as high a concentration of the vector as possible in order thereby to achieve the maximum possible binding of vectors to the target cells by means of the target cell-specific ligands. In a particularly preferred embodiment, these non-viral carriers (a) are cationized to enable them to complex with the negatively charged DNA.
In addition, the novel vectors may contain a fusion protein that is responsible for penetration of the vector out of the endosomes or lysosomes and into the cytoplasm of the host cell. Within the context of the present invention, fusion proteins are defined as those proteins that enable the vector to enter the cytoplasm of the target cell. Fusion proteins of this nature are known, especially from viral sources.
The gene (d) that is to be introduced by the novel vectors can be in the form of a nucleic acid containing the corresponding gene which, if necessary, is provided with the appropriate regulatory regions such as promoters, etc. In a preferred embodiment, the gene that is to be introduced is in the form of a plasmid.
The non-viral carriers for the gene, that can be employed in accordance with the invention, are known in the art (for reviews, see Cotten et al., Curr. Biol., 4: 705 (1993); Behr, Acc. Chem. Res., 26: 274 (1993) ; Felgner, Adv. Deliv. Rev., 5: 163 (1990); Behr, Bioconjugate Chem., 5: 382 (1994); Ledley, Hum. Gene Ther. 6: 1129 (1995) all of which are hereby incorporated by reference). Those that are preferably employed within the context of the present invention are liposomes, cationic liposomes that are prepared using cationic lipids such as stearyl amines in a mixture with neutral phospholipids, dioctadecyldimethylammonium bromide (DDA) in a mixture with neutral phospholipids, N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium bromide (DOTMA), 3xcex2-[N-(Nxe2x80x2,Nxe2x80x2-dimethylaminoethane)carbamoyl]cholesterol (DC-Chol), 1,2-dimyristyloxypropyl-3-dimethylhydroxyethylammonium bromide (DMRIE), dimethyldioctadecylammonium bromide (DDAB) and 1,2-dioleoyloxy-3-(trimethylammonio)propane (DOTAP).
Cationic polypeptides and proteins, such as polylysine, protamine sulfates, histones, polyornithine and polyarginine, are also suitable as non-viral carriers, as are cationic amphiphilic lipopolyamines such as dioctadecylamidoglycylspermine (DOGS), dipalmitoylphosphatidylethanolamidospermine (DPPES), N-t-butyl-Nxe2x80x2-tetradecyl-3-tretradecylaminopropionamide (diC14-amidine), DoTB, ChoTB, DoSC, ChoSC, LPLL, DEBDA, DTAB, TTAB, CTAB or TMAG,or cationic polysaccharides such as diethylaminoethyldextran, and also cationic organic polymers such as Polybrene.
In a further preferred embodiment, formulations of cationic lipids and lipopolyamines (complexed with DNA) can, for the purpose of increasing the transfection rate, be supplemented by admixing neutral phospholipids such as dioleoylphosphatidylethanolamine (DOPE).
In a particularly preferred embodiment, the non-viral carriers are compounds whose parent substances are cationic or cationized water-soluble polypeptides, proteins, glycoproteins, lipoproteins or polysaccharides that exhibit amphiphilic behavior due to the introduction of (where appropriate additional) lipophilic groups. The parent substances are preferably water-soluble carriers, such as proteins, glycoproteins, lipoproteins or polysaccharides. In a particularly preferred embodiment, the carrier is albumin or xylan.
Structural units that have a positive charge and that can be bound to the parent substance are suitable for use as cationic groups. Preferably, the cationic groups are structural units that exhibit amino, guanidino or imidazolyl functions under physiological conditions. The cationic groups can be coupled to the parent substances using well-known methods of conjugation. For example, coupling with diamines, such as ethylenediamine or hexamethylenediamine, is suitable for amino functions. Free amino groups can also be methylated with methyl iodide, or unilaterally reacted glutaraldehyde groups can be reacted with Girard T reagent [see, e.g., Roser, Dissertation, University of Basle (1990) hereby incorporated by reference].
Guanidino and imidazolyl groups may be introduced by coupling to the corresponding basic amino acids using the methods that are described below. Preference is given to coupling to albumin using glutaraldehyde (Roser, above).
The number of cationic groups that have to be introduced depends on the magnitude of the anionic charge of the gene or the nucleotide sequence with which the carrier is to be complexed. Preferably, the complex as a whole should have a neutral or cationic charge.
All structural units that lead to an increase in solubility in organic solvents, for example octanol, are regarded as lipophilic groups. Unsaturated fatty acids, for example oleic acid, that are used as esters, acid chlorides and acid anhydrides are, in particular, regarded as lipophilic groups. Lipophilic groups are introduced using well-known methods of conjugation, for example by acylation, i.e. the reaction of acid chorides, acid anhydrides and esters with primary and secondary amines, as described in Seebach, Angew., Chemie, 81: 690 (1969) and Satchell, Quart. Rev., 17: 160 (1963) hereby incorporated by reference. The number of lipophilic groups that have to be introduced depends on the degree of lipophilicity of the parent substance.
A large number of molecules can be used as tissue-targeting ligand (b). As described above, the choice of suitable ligand depends on the target cells for which the vector is to be specific. As a rule, the ligands are proteins, polypeptides or glycoproteins that exhibit a high specific affinity for membrane constituents on selected cells (target cell). Depending on the target cell, ligands that can be used within the context of the present invention include:
1) Ligands for Endothelial Cells
a) Non-viral Ligands (b)
Substances that preferably bind to the surface of endothelial cells, in particular proliferating endothelial cells, are used as ligands. These substances include antibodies or antibody fragments that are directed against membrane structures of endothelial cells, as have been described, for example, by Burrows et al. (Pharmac. Ther., 64: 155 (1994)); Hughes et al. (Cancer Res., 49: 6214 (1989)) and Maruyama et al., (PNAS-USA, 87: 5744 (1990) all of which are hereby incorporated by reference. In particular, these substances include antibodies against the VEGF receptors.
Murine monoclonal antibodies should preferably be employed in humanized form. Humanization is effected in the manner described by Winter et al. (Nature, 349: 293 (1991)) and Hoogenbooms et al. (Rev. Tr. Transfus. Hemobiol., 36: 19 (1993) both of which are hereby incorporated by reference). Antibody fragments are prepared by routine methods, for example in the manner described by Winter et al. above; Hoggenbooms et al. above; Girol, Mol. Immunol., 28: 1379 (1991) or Huston et al., Intern. Rev. Immunol., 10: 195 (1993) all of which are hereby incorporated by reference.
In addition, the ligands include all active compounds which bind to membrane structures or membrane receptors on endothelial cells. For example, these active compounds include kinins, and analogs and homologs of kinins, that bind to kinin receptors, and also substances that contain mannose terminally, and also IL-1 or growth factors, or their fragments or constituent sequences thereof, which bind to receptors which are expressed by endothelial cells, such as HGF, PDGF, bFGF, VEGF or TGFxcex2 (Pusztain et al., J. Pathol., 169: 191 (1993) hereby incorporated by reference). Furthermore, these active compounds include adhesion molecules which bind to activated and/or poliferating endothelial cells. Adhesion molecules of this nature, for example Slex, LFA-1, MAC-1, LECAM-1 or VLA-4, have already been described (reviews in Augustin-Voss et al., J. Cell. Biol., 119: 483 (1992); Pauli et al., Cancer Metast. Rev., 9: 175 (1990); Honn et al., Cancer Metast. Rev., 11: 353 (1992) hereby incorporated by reference).
b) Viral-derived Ligands
The ligands within the meaning of this invention also include glycoproteins from the coats of viruses that possess a tropism for endothelial cells. Examples of these viruses are:
filoviruses, for example
Marburg virus
with its coat protein GP (glycoprotein) and sGP (second glycoprotein)
(Kiley et. al., J. General Virology, 69: 1957 (1988); Will et al., J. Virol., 67: 1203 (1993); Schnittler et al., J. Clin. Invest., 91: 1301 (1993); Feldmann et al., Virus Res. 24: 1 (1992) all of which are hereby incorporated by reference)
or Ebola virus
in each case with its coat protein GP and sGP
(Schnittler et al., J. Clin. Invest., 91: 1301 (1993); Volchov et al., Virol., 214: 421 (1995); Jahrling et al., Lancet, 335: 502 (1990); Feldmann et al., Arch. Virol., 7: 81 (1993); Geisbert et al., J. Comp. Path., 106: 137 (1992) all of which are hereby incorporated by reference)
cytomegalovirus,
particularly with its gB protein
(Waldman et al., Transplant. Proc., 27: 1269 (1995); Sedmak et al., Transplant, 58: 1379 (1994); Sedmak et al., Archives Virol, 140: 111 (1995); Koskines, Transplant, 56: 1103 (1993); Scholz et al., Hum. Immunol. 35: 230 (1992); Alcami et al., J. Gen. Virol., 72: 2765 (1991); Poland et al., J. Infect. Dis., 162: 1252 (1990); Ho et al., J. Infect. Dis., 150: 956 (1984); Spaete et al., J. Virol., 64: 2922 (1990) all of which are hereby incorporated by reference)
herpes simplex virus type I
(Etingin et al., PNAS 90, 5153 (1993); Key et al., Lab. Invest., 68: 645 (1993); Kubota et al., J. Immunol., 138: 1137 (1987) all of which are hereby incorporated by reference)
the HIV-1 virus
(Scheylovitova et al., Arch. Virol., 140: 951 (1995); Lafon et al., AIDS, 8: 747 (1994); Re et al., Microbiologica, 14: 149 (1991) all of which are hereby incorporated by reference)
measles virus
(Mazure et al., J. Gen. Virol., 75: 2863 (1994) hereby incorporated by reference)
Hantaan virus
(Pensiero et al., J. Virol., 66: 5929 (1992); Zhu, Chinese Med. J., 68: 524 (1988) both of which are hereby incorporated by reference)
alphaviruses, such as Semliki Forest virus
(Jakob, J. Med. Microbiol., 39: 26 (1993) hereby incorporated by reference)
epidemic hemorrhagic fever virus
(Yi, Chinese J. Pathol., 21: 177 (1992) hereby incorporated by reference)
poliovirus
(Condere et al., Virol., 174: 95 (1990) hereby incorporated by reference)
enteroviruses (such as Echo 9, Echo 12, Coxsackie B3)
(Kirkpatrick et al., Am. J. Pathol., 118: 15 (1985) hereby incorporated by reference).
2) Ligands for Smooth Muscle Cells
a) Non-viral Ligands (b)
Examples of non-viral ligands (b) that may be used are antibodies or antibody fragments which are directed against membrane structures of smooth muscle cells. These include:
the antibody 10F3 (Printseva et al., Exp. Cell Res., 169: 85 (1987); American J. Path. 134, 305 (1989) both of which are incorporated herein by reference)
Antibodies against actin
Antibodies against angiotensin II receptors
Antibodies against receptors for growth factors or antibodies directed, for example, against
EGF receptors
PDGF receptors
FGF receptors
against endothelin A receptors.
In addition, these ligands include all active substances that bind to membrane structures or membrane receptors on smooth muscle cells (reviews in Pusztai et al., J. Pathol., 169: 191 (1993), Harris, Current Opin. Biotechnol., 2: 260 (1991) all of which are hereby incorporated by reference). For example, these active substances include growth factors or their fragments, or constituent sequences thereof, which bind to receptors that are expressed by smooth muscle cells, for example
PDGF
EGF
TGFxcex2
TGFa
FGF
endothelin A
b) Viral-derived Ligands (b)
However, ligands within the meaning of this invention include, in particular, glycoproteins from the coats of those viruses which possess a tropism for smooth muscle cells. An example of these viruses is cytomegalovirus (Speir et al., Science 265, 391: (1994) hereby incorporated by reference).
3) Choice of the Ligand for Macrophages and Lymphocytes
a) Non-viral Ligands (b)
The ligands that bind specifically to the surface of macrophages and lymphocytes include antibodies or antibody fragments that are directed against membrane structures of immune cells, as described, for example, by Powelson et al., Biotech. Adv., 11: 725 (1993) hereby incorporated by reference.
In addition, the ligands also include monoclonal or polyclonal antibodies or antibody fragments which bind, by their constant domains, to Fc-g receptors or FC-e receptors of immune cells (Rojanasakul et al., Pharm. Res., 11: 1731 (1994) hereby incorporated by reference); these include, in particular, the Fc fragment of human polyclonal immunoglobulin. Fc fragments of this nature are prepared, for example, in accordance with the methods of Haupt et al., Klin. Wschr., 47: 270 (1969); Kranz et al., Dev. Biol. Standard, 44: 19 (1979); Fehr et al., Adv. Clin. Pharmac., 6: 64 (1974); and Menninger et al., Immunochem. 13: 633 (1976) all of which are hereby incorporated by reference.
These ligands furthermore include all substances that bind to membrane structures or membrane receptors on the surface of immune cells. Examples of these substances are the cytokines IL-1, IL-2, IL-3, IL-4, IL-6, IL-10, TNFa, GM-CSF and M-CSF, and also growth factors such as EGF, TGF, FGF, IGF or PDGF, HGF, or their fragments or constituent sequences thereof, which bind to receptors which are expressed by cells of this nature.
These ligands also include ligands that bind to cell membrane structures such as the mannose 6-phosphate receptor on macrophages in spleen, liver, lung and other tissues. These ligands and membrane structures have been reviewed by Perales et al., Eur. J. Biochem., 226: 255 (1994) hereby incorporated by reference.
b) Viral Ligands
However, the ligands within the meaning of this section include, in particular, glycoproteins from the coats of those viruses which possess a tropism for lymphocytes and/or macrophages.
Examples of viruses that infect macrophages include:
HIV-1,
particularly those strains having mutations in the V3 region of gp120 which lead to increased binding to macrophages, for example as described by Kim et al., J. Virol., 69: 1755 (1995); Valentin et al., J. Virol., 68: 6684 (1994); Collin et al., J. Gen. Virol., 75: 1597 (1994); Shoida et al., PNAS, 89: 9434 (1992); Chesebro et al. , J. Virol., 66: 6547, (1992); Shaw et al., J. Virol., 66: 2577 (1992); Liu et al., J. Virol., 64: 6148 (1990); Broder et al., PNAS, 92: 9004 (1995); Cangue et al., Virol., 208:, 779 (1995), all of which are hereby incorporated by reference.
HIV-2
(Valentin et al., J. Virol., 68: 6684 (1994) hereby incorporated by reference)
hantaviruses, for example the Punmala virus
(Temonen et al., Virol., 206: 8 (1995), hereby incorporated by reference
cytomegalovirus
(Fajac et al., Am. J. Resp. Crit. Care Med., 149: 495 (1994); Kondo et al., PNAS, 91: 11879 (1994); Ibanez et al., J. Virol., 65: 6581 (1991) all of which are hereby incorporated by reference)
respiratory syncytial virus
(Becker et al., Am. J. Resp. Cell Mol. Biol., 6: 369 (1992); Roberts, Infect. Immun., 35: 1142 (1982) both of which are hereby incorporated by reference)
herpes simplex virus
(Plaeger-Marshall et al., Pediatric Res., 26: 135 (1989) hereby incorporated by reference)
filoviruses
(Schnittler et al., J. Clin. Invest., 91: 1301 (1993); Zaki, Eur. Conf. Tropical Med., p2 (A22), Hamburg, Germany (1995) both of which are hereby incorporated by reference.
Examples of viruses that infect lymphocytes include:
varicella zoster virus (VZV)
VZV infects T cells in particular
(Moffat et al., J. Virol., 69: 5236 (1995) hereby incorporated by reference)
herpesvirus 6 (HHV-6).
HHV-6 infects T cells in particular
(Takahashi et al., J. Virol., 63: 3161 (1989) hereby incorporated by reference; Lusso et al., J. Exp. Med., 181: 1303 (1995); Frenkel et al., Adv. Exp. Med. Biol., 278: 1 (1990) hereby incorporated by reference)
rabies virus
Rabies virus coat protein binds, in particular, to TH2 cells (Martinez-Arends et al., Clin. Immunol. Immunopath., 77: 177 (1995) hereby incorporated by reference)
HIV-1
The gp 120 glycoprotein binds preferentially to the CD4 molecule of T cells
(Heinkelein et al., J. Virol., 69: 6925 (1995) hereby incorporated by reference)
HTLV-II
HTLV-II infects B cells in particular
(Casoli et al., Virol., 206: 1126 (1995) hereby incorporated by reference)
HTLV-I
HTLV-I infects T cells in particular
(Persaud et al., J. Virol., 69: 6297 (1995); Boyer et al., Cell Immunol., 129: 341 (1990) both of which are hereby incorporated by reference)
influenza C viruses
Influenza C viruses bind, by way of the hemagglutininesterase fusion (HEF) protein, to N-acetyl-9-xcex2-acetylneuraminic acid (Neu 5,9 Ac), which occurs preferentially on B lymphocytes and less, or not at all, on T lymphocytes
(Herrler et al., EMBO-J., 4: 1503 (1985); Kamerling et al., BBA, 714: 351 (1982); Rogers et al., J. Biol. Chem., 261: 5947 (1986) hereby incorporated by reference)
influenza C viruses having a mutation in nucleotide position 872
(which encodes position 284 of the amino acid sequence of the HEF), for example a replacement of the threonine by isoleucine.
The surface protein HEF having this mutation has a markedly greater affinity for the N-acetyl-9-0-acetylneuraminic acid receptor than does the wild-type virus.
(Szepanski et al., Virol., 188: 85 (1992) hereby incorporated by reference)
HEF cleavage products of influenza C virus which contain the structure for binding to N-acetyl-9-xcex2-acetylneuraminic acid.
This binding structure is defined by the catalytic triad serine 71, histidine 368 or 369 and aspartic acid 261
(Pleschka et al., J. Gen. Virol., 76: 2529 (1995) hereby incorporated by reference)
Epstein-Barr virus.
EBV infects B cells in particular
(Miller-Yale, J. Biol. Med., 55: 305 (1982); Garzelli et al., Immunol. Lett., 39: 277 (1994); Counter et al., J. Virol., 68: 3410 (1994); Wang et al., J. Virol., 62: 4173 (1988) all of which are incorporated herein by reference)
herpes simplex virus 2.
HSV-2 infects T cells in particular (Kucera et al., Viral Immun., 2: 11 (1989) hereby incorporated by reference)
measles virus
(Jacobson et al., J. Gen. Virol., 63: 351 (1982) hereby incorporated by reference)
4) Choice of the Ligands for Glial Cells
a) Non-viral Ligands (b)
Substances that bind to the surface of glial cells are also to be regarded as ligands. These substances include antibodies or antibody fragments that are directed against membrane structures of glial cells, as reported, for example, by Mirsky et al., (Cell and Tissue Res., 240: 723 (1985)); by Coakham et al. , (Prog. Exp. Tumor Res., 29: 57 (1985)) and by McKeever et al. (Neurobiol., 6: 119 (1991) all of which are hereby incorporated by reference). These membrane structures furthermore include neural adhesion molecules such as N-CAM, in particular its polypeptide chain C (Nybroe et al., J. Cell Biol., 101: 2310 (1985) hereby incorporated by reference).
These ligands furthermore include all active compounds that bind to membrane structures or membrane receptors on glial cells. Examples of these active compounds are substances which carry mannose terminally and bind to the mannose 6-phosphate receptor (Perales et al., Eur. J. Biochem., 226: 225 (1994), insulin and insulin-like growth factor (Merrill et al., J. Clin. Endocrin. Metab., 71: 199 (1990)), PDGF (Ek et al., Nature, 295: 419 (1982), hereby incorporated by reference, and those fragments of these growth factors which bind to the affiliated membrane receptors.
b) Viral-derived Ligands (b)
The ligands within the meaning of the invention include, in particular, glycoproteins from the coats of those viruses that possess a tropism for glial cells.
Examples of these viruses are:
HIV-1 subtype JRF1
(Sharpless et al., J. Virol. 66, 2588 (1992), hereby incorporated by reference
herpes simplex virus I
(Xie et al., Eye Science (Yen Ko Hsueh Pao) 10, 67 (1994); Genis et al., J. Exp. Med. 176, 1703 (1992) both of which are hereby incorporated by reference)
5) Non-viral Ligands for Hematopoietic Cells
The ligands include antibodies or antibody fragments which are directed against receptors which are expressed, e.g., on blood cells, that are only slightly differentiated.
Antibodies of this nature have been described for the following receptors include:
stem cell factor receptor
IL-1 receptor (Type I)
IL-1 receptor (Type II)
IL-3 receptor a
IL-3 receptor xcex2
IL-6 receptor
GM-CSF receptor.
In addition, these ligands also include monoclonal or polyclonal antibodies or antibody fragments that bind, by their constant domains, to FC-g receptors of immune cells (Rojanasakul et al., Pharm. Res. 11, 1731 (1994)).
The ligands also include substances that bind to membrane structures or membrane receptors on the surface of blood cells which are only slightly differentiated. Examples of these substances are growth factors such as SCF, IL-1, IL-3, IL-6 or GM-CSF, or their fragments or constituent sequences thereof, which bind to receptors which are expressed by cells of this nature.
6) Non-viral Ligands for Leukemia Cells and Tumor Cells
The ligands that bind to the surface of leukemia cells include antibodies or antibody fragments which are directed against membrane structures of leukemia cells. A large number of such monoclonal antibodies have already been described for diagnostic and therapeutic methods (Reviews in Kristensen, Danish Medical Bulletin, 41: 52 (1994); Schranz, Therapia Hungarica, 38: 3 (1990); Drexler et al., Leuk. Rex., 10: 279 (1986); Naeim, Dis. Markers, 7: 1 (1989); Stickney et al., Current Op. Oncol., 4: 847 (1992); Drexler et al., Blut, 57: 327 (1988); Freedment et al., Cancer Invest., 9: 69 (1991) all of which are incorporated herein by reference). The following monoclonal antibodies, or their antigen-binding antibody fragments, are, for example, suitable for use as ligands, depending on the type of leukemia:
All of the above references are hereby incorporated by reference.
The non-viral ligands for tumor cells include antibodies, and fragments of these antibodies, which are directed against membrane structures on tumor cells. Antibodies of this nature have been reviewed, for example, by Sedlacek et al., Contrib. to Oncol., 32: Karger Verlag, Munich (1988) and Contrib. to Oncol., 43: Karger Verlag, Munich (1992) both of which are hereby incorporated by reference.
Additional examples are antibodies against:
sialyl Lewis
(Ohta et al., Immunol. Lett., 44: 35 (1995) hereby incorporated by reference)
peptides on tumors which are recognized by T cells
(Maeurer et al., Melanoma Res., 6: 11 (1996); Coulie, Stem Cells, 13: 393 (1995); Stoh et al., J. Biochem, 119: 385 (1996); Slingluff et al., Curr. Opin. Imunol., 6: 733 (1994) all of which are hereby incorporated by reference)
proteins which are expressed from oncogenes
(Cheever et al., Immunol. Rev., 145: 33 (1995); Talarico et al., PNAS, 87: 4222 (1990))
gangliosides such as GD3, GD2, GM2, 9-0-acetyl GD3 and fucosyl GM1
(Helling et al., Cancer Res., 55: 2783 (1995); Livingston et al., Vaccine, 11: 1199 (1993); Vaccine, 12: 1275 (1994); Livingston et al., Cancer Immunol. Immunother., 29: 179 (1989); Gnewuch et al., Int. J. Cancer, 8: 125 (1994); Jennemann et al., J. Biochem., 115: 1047 (1994); Ravindranath et al., Cancer Res., 49: 3891 (1989) all of which are hereby incorporated by reference)
blood group antigens and their precursors
(Springer et al., Cancer, 37: 169 (1976); Carbohydrate Res., 179: 271 (1988); Molec. Immunol., 26: 1 (1989); Fung et al., Cancer Res., 50: 4308 (1990) all of which are hereby incorporated by reference)
antigens on polymorphic epithelial mucin
(PEM; Burchell et al., Cancer Surreys, 18: 135 (1993) hereby incorporated by reference)
antigens on heat shock proteins
(Blackere et al., J. Immunother., 14: 352 (1993) hereby incorporated by reference).
The murine monoclonal antibodies are preferably to be employed in humanized form. The humanization is effected as already described. As already described, antibody fragments are prepared in accordance with the state of the art.
The ligands additionally include all active compounds which bind to membrane structures or membrane receptors of leukemia cells or tumor cells. Examples of these active compounds are steroid hormones or peptide hormones, or else growth factors, or their fragments or constituent sequences thereof, which bind to receptors which are expressed by leukemia cells or tumor cells.
Growth factors of this nature have already been described (Reviews in Cross et al., Cell, 64: 271 (1991); Aulitzky et al., Drugs, 48: 667 (1994); Moore, Clin. Cancer Res., 1: 3 (1995); Van Kooten et al., Leuk. Lymph. 12: 27 (1993) all of which are hereby incorporated by reference). For example, they include:
IFNa in non-Hodgkin lymphomas
IL-2, particularly in T cell leukemias
FGF in T cell monocytic, myeloid, erythroid and megakaryoblastic leukemias
TGFxcex2 in leukemias
retinoids, e.g. xe2x80x9cretinoic acidxe2x80x9d in acute promyelocytic leukemia.
7) Non-viral Ligands (b) for Infected Cells
Ligands for the therapy of infectious diseases include antibodies or antibody fragments that are directed against the agents causing the infection. For example, in the case of viral infections, these are the viral antigens which are expressed on the cell membrane of virus-infected cells.
Antibodies of this nature have been described, for example, for cells that are infected with the following viruses:
HBV
HCV
HSV
HPV
HIV
EBV
HTLV.
In addition, the ligands also include monoclonal or polyclonal antibodies, or antibody fragments, which bind, by their constant domains, to Fc-g receptors or FC-e receptors of immune cells.
The murine monoclonal antibodies are preferably to be employed in humanized form. The humanization is effected as already described.
The ligands furthermore include all substances which bind to membrane structures or membrane receptors on the surface of virus-infected cells. Examples of these substances include growth factors such as cytokines, EGF, TGF, FGF, HGF or PDGF, or their fragments or constituent sequences thereof, which bind to receptors which are expressed by cells of this nature.
8) Ligands for Other Parenchymal Cells
a) Non-viral Ligands (b)
These include ligands that bind to cell membrane structures that are selective for particular tissues. Examples of these ligands are:
These ligands and membrane structures have been reviewed by Perales et al., Eur. J. Biochem., 226: 255 (1994) hereby incorporated by reference.
b) Viral-derived Ligands (b)
However, within the meaning of the invention, these ligands include, in particular, glycoproteins from the coats of viruses which possess a tropism for selected cells, for example for
bronchial epithelial cells
respiratory syncytial virus
(Becker et al., Am. J. Resp. Cell Mol. Biol., 6: 369 (1992) hereby incorporated by reference)
liver cells
hepatitis C virus
(Uchida et al., Pathol. Internat., 44: 832 (1994); Carloni et al., Arch. Virol., 8: 31 (1993); Prince et al., Curr. Stud. Hemat. Blood Trans., 61: 195 (1994) all of which are hereby incorporated by reference)
filoviruses
liver cells bind the Marburg virus, for example, by way of the asialoglycoprotein receptor,
(Becker et al., J. Gen. Virol., 76: 393 (1995) hereby incorporated by reference),
hepatitis B virus
liver cells bind, preferentially by way of the asialoglycoprotein receptor, to the preS2 and preS1 domain of HBV (Shimizu et al., J. Med. Virol., 20: 313 (1986); Treichel et al., J. Gen. Virol., 75: 3021 (1994); Gerlich et al., J. Hepat., 17/3: 10 (1993); Gripon et al., Virol., 192: 534 (1993); Pontisso et al., Hepatol., 14: 405 (1991); Ochiya et al., PNAS, 86: 1875 (1989) all of which are hereby incorporated by reference)
hepatitis D virus
(Colombo et al., J. Hepatol., 12: 64 (1991) hereby incorporated by reference)
liver sinusoidal cells
hepatitis V virus
HBV is bound by way of fibronectin
(Budhowska et al., J. Virol., 69: 840 (1995) hereby incorporated by reference).
9) Ligands for the Prophylaxis of Infectious Diseases
For the prophylaxis of infectious diseases, all substances which bind to cell membrane structures of macrophages and/or lymphocytes are suitable for use as ligands. Ligands of this nature have already been described.
Viral-derived ligands are isolated either by dissolving the envelope proteins from an enriched viral preparation with the aid of detergents (such as xcex2-D-octylglucopyranoside) and separating them by centrifugation (review in Mannino et al., Bio-Techniques, 6: 682 (1988) hereby incorporated by reference) or else using molecular biological methods which are known to the skilled person, as have been described in the literature cited under II/2/a-h), for example by Pleschka et al. (J. Gen. Virol., 76: 2529 (1995)) and by Szepanski et al. (Virol., 188: 85 (1992) hereby incorporated by reference) for the HEF glycoprotein.
Within the context of the present invention, proteins are used that possess fusiogenic properties. Proteins of this nature are able to fuse directly with cell membranes. A number of viruses, for example paramyxoviruses, retroviruses and herpesviruses, possess fusiogenic coat proteins (Gaudin et al., J. Gen. Virol., 76: 1541 (1995) hereby incorporated by reference).
Within the meaning of this invention, fusiogenic proteins also include those glycoproteins that fuse with the cell membrane or endosomes only after having been internalized in endosomes and only at an acid pH.
A number of viruses possess glycoproteins that are responsible both for the adhesion of the virus and also, subsequently, for the cell membrane fusion (Gaudin et al., J. Gen. Virol., 76: 1541 (1995) all of which are hereby incorporated by reference).
Proteins of this nature are formed, for example, by alphaviruses, rhabdo- viruses and orthomyxoviruses.
Viral fusion proteins within the meaning of the invention have been reviewed by Hughson, Current Biol., 5: 265 (1995); Hoekstra, J. Bioenergetics Biomembranes, 22: 675 (1990); and White, Ann. Rev. Physiol., 52: 675 (1990) all of which are hereby incorporated by reference).
Examples of fusion proteins within the meaning of this invention are:
the hemagglutinin of influenza A or B viruses, in particular the HA2 component
(Stegmann et al., J. Biol. Chem., 266: 18404 (1991); Klenk et al., Virol., 68: 426 (1975); Lazarowitz et al., Viral., 68: 440 (1975); Skehel et al., PNAS, 79: 968 (1982); Bosch et al., Virol., 113: 725 (1981) all of which are hereby incorporated by reference)
the M2 protein of influenza A viruses
(Sugrue et al., Virol., 180: 617 (1991); Lamb et al., Cell, 40: 627 (1985); Pinto et al, Cell, 69: 517 (1992); Zebedee et al., J. Virol., 56: 502 (1985); Black et al., J. Gen. Virol., 74: 1673 (1993); Wharton et al., J. Gen. Virol., 75: 945 (1994) all of which are hereby incorporated by reference) either alone or employed in combination (Ohuchi et al., J. Virol., 68: 920 (194) which is hereby incorporated by reference) with the hemagglutinin of influenza or with mutants of neuraminidase of influenza A which lack enzyme activity but which bring about hemagglutination. (Hausmann et al., J. Gen. Virol., 76: 1719 (1995), hereby incorporated by reference)
peptide analogs of the influenza virus hemagglutinin
(Wharton et al., J. Gen. Virol., 69: 1847 (1988) hereby incorporated by reference)
the HEF protein of influenza C virus
The fusion activity of the HEF protein is activated by cleaving the HEFo into the HEF1 and HEF2 subunits
(Herrler et al., J. Gen. Virol., 69: 839 (1988); Kitane et al., Arch. Virol., 73: 357 (1982); Ohuchi et al., J. Virol., 42: 1076 (1982) hereby incorporated by reference)
the transmembrane glycoprotein of filoviruses, such as
Marburg virus
(Feldmann et al., Viral., 182: 353 (1991); Will et al., J. Virol., 67: 1203 (1993); Kiley et al., J. Gen. Virol., 69: 1957 (1988); Geyer et al., Glycobiol., 2: 299 (1992) hereby incorporated by reference)
Ebola virus
(Elliott et al., Virol., 147: 169 (1985); Cox et al., J. Infect. Dis., 147: 272 (1983); Kiley et al., J. Gen. Virol., 69: 1957 (1988); Feldmann et al., Arch. Virol., 7: 81 (1993); Volchkov et al., Virol., 214: 421 (1995) all of which are hereby incorporated by reference)
the transmembrane glycoprotein of rabies virus
(Whitt et al., Virol., 185: 681 (1991); Gaudin et al., J. Virol., 65: 4853 (1991); 67: 1365 (1993); Virology, 187: 627 (1992) all of which are hereby incorporated by reference)
the transmembrane glycoprotein (G) of vesicular stomatitis virus
(Balch et al., J. Biol. Chem., 261: 14681 (1986); Kreis et al., Cell, 46: 929 (1986); Doms et al., J. Cell Biol., 105: 1957 (1987); Zhang et al., J. Virol., 68: 2186 (1994); Ohnishi, Curr. Topics Membr. Transp., 32: 257 (1988); Li et al., J. Virol., 67: 4070 (1993); Zagouras et al., J. Virol., 65: 1976 (1991); Herrmann et al., Biochem., 29: 4054 (1990) all of which are hereby incorporated by reference)
the fusion protein of HIV virus, in particular the gp41 component
(Stareich et al., Cell, 45: 637 (1986); Kowalski et al., Science, 237: 1351 (1987); Gallaker et al., Cell, 50: 327 (1987) all of which are hereby incorporated by reference)
the fusion protein of Sendai virus, in particular the F1 component
(Blumberg et al., J. Gene Virol., 66: 317 (1985); Sechoy et al., J. Biol. Chem., 262: 11519 (1987); Homma and Ohuchi, J. Virol., 12: 1457 (1973); Scheid and Choppin, Virol., 57: 470 (1974) all of which are hereby incorporated by reference)
the transmembrane glycoprotein of Semliki Forest virus, in particular the E1 component
(Omar et al., Virol., 166: 17 (1988); Nieva et al., EMBO-J., 13: 2707 (1994); Phalen et al., J. Cell Biol., 112: 615 (1991); Lobigs et al., J. Virol., 64: 1233+5214 (1990);, Kenney et al., Structure, 2: 823 (1994); Garoff et al., Nature, 288: 236 (1980); Levy-Mintz et al., J. Virol., 65: 4292 (1991) all of which are incorporated herein by reference)
the transmembrane glycoprotein of tickborn encephalitis virus
(Guirakhoo et al., Virol., 169: 90 (1989); J. Gen. Virol., 72: 1323 (1991); Heinz et al., Virol., 198: 109 (1994) all of which are incorporated herein by reference)
the fusion protein of human respiratory syncytial virus (RSV), in particular the gp37 component
(Collins et al., PNAS, 81: 7683 (1984); Elango et al., Nucl. Acids Res., 13: 1559 (1985) both of which are incorporated herein by reference)
Viral-derived fusion proteins are isolated either by dissolving the coat proteins from an enriched viral preparation with the aid of detergents (such as xcex2-D-octylglucopyranoside) and separating them by centrifugation (see, e.g., review in Mannino et al., Bio/Techniques, 6: 682 (1988) hereby incorporated by reference) or else using molecular biological methods which are known to the skilled person. Examples of the preparation of fusion proteins have already been described for:
influenza hemagglutinin
(Bullough et al., J. Mol. Biol., 236: 1262 (1994); Nature, 371: 37 (1994); Daniels et al., Cell, 40: 431 (1985); Godley et al., Cell, 68: 635 (1992); White et al., Nature, 300: 658 (1982); Wiley et al., Ann. Rev. Biochem., 56: 365 (1987); Kawaoka et al., PNAS, 85: 321 (1988); Kuroda et al., J. Virol., 63: 1677 (1989), EMBO-J., 5: 1359 (1986); Naeve et al., Virol., 129: 298 (1983); Porter et al., Nature, 282: 471 (1972); Hughson, Curr. Biol., 5: 265 (1995) all of which are incorporated herein by reference)
the M2 protein of influenza V
(Black et al., J. Gen. Virol., 74: 1673 (1993); Pinto et al., Cell, 69: 517 (1992); Zebedee et al., J. Virol., 56: 502 (1985) all of which are incorporated herein by reference)
the HEF protein of influenza C
(Pfeifer et al., Virus. Res., 1: 281 (1984); Herrler et al., Virol., 113: 439 (1981) both of which are incorporated herein by reference)
the transmembrane glycoprotein of filoviruses, such as
Marburg virus
(Will et al., J. Virol., 67: 1203 (1993); Feldmann et al., Virus Res., 24: 1 (1992) both of which are incorporated herein by reference)
Ebola virus
(Volchkow et al., FEBS Lett., 305: 181 (1992); Virol., 214: 421 (1995); Sanchez et al., Virus Res., 29: 215 (1993); Virol., 157: 414 (1987); Eliott et al., Virol., 163: 169 (1985) all of which are incorporated herein by reference)
the transmembrane glycoprotein of rabies virus
(Gaudin et al., J. Virol., 65: 4853 (1991); Virol., 187: 627 (1992); Rose et al., J. Virol., 43: 361 (1982); Witte et al., Virol., 185: 681 (1991) all of which are incorporated herein by reference)
the transmembrane glycoprotein of vesicular stomatitis virus
(Li et al., J. Virol., 67: 4070 (1993); Riedel et al., EMBO-J., 3: 1477 (1984); Lyles et al., Biochem. 29: 2442 (1990); Metsikko et al., EMBO-J., 5: 3429 (1986) all of which are incorporated herein by reference)
the transmembrane glycoprotein of Semliki Forest virus
(Garoff et al., Nature, 288: 236 (1980); Kielian et al. , J. Virol., 64: 4614 (1990); Kondor-Koch, J. Cell Biol., 97: 644 (1983) all of which are incorporated herein by reference)
the transmembrane glycoprotein of tickborn encephalitis virus
(Guirakkoo et al., J. Gen. Virol., 72: 1323 (1991); Heinz et al., Virol., 198: 109 (1994) both of which are incorporated herein by reference).
Molecules possessing fusiogenic properties are furthermore:
peptides which contain the translocation domain (domain II) of Pseudomonas exotoxin A (Weis et al., Cancer Res., 52: 6310 (1992)); Fominaga et al., J. Biol. Chem., 271: 10560 (1996) both of which are incorporated herein by reference)
peptides which contain the peptide (SEQ ID NO:5)
GLFEALLELLESLWELLLEA
(Gottschalk et al., Gene Ther., 3: 448 (1996) hereby incorporated by reference)
peptides which contain the peptide (SEQ ID NO:6)
AALAEA[LAEA]4LAAAAGC (Acm)
(Wang et al., Technol. Advances in Vector Syst. for Gene Ther., May 6-7, 1996, Coronado, IBC Conference, hereby incorporated by reference)
peptides which contain the peptide (SEQ ID NO:7)
FAGV-VLAGAALGVAAAAQI
of the fusion protein of measles virus
(Yeagle et al. , Biochem. Biophys. Acta 1065, 49: (1991) hereby incorporated by reference)
peptides which contain the peptide (SEQ ID NO:8)
GLFGAIAGFIEGGWWGMIDG
of the HA2 protein of influenza A (Lxc3xcneburg et al., J. Biol. Chem. 270: 27606 (1995) hereby incorporated by reference)
peptides which contain the peptide (SEQ ID NO:9)
GLFGAIAGFIENGWEGMIDGGLFGAIAGFIENGWEGMIDG
(Burger et al., Biochem., 30: 11173 (1991) hereby incorporated by reference) or the peptide(SEQ ID NOS:10-21)
GLFGAIAGFIE;
ALFGAIAGFIE;
LFLGAIAGFIE;
LLLGAIAGFIE;
LILGAIAGFIE;
GIFGAIAGFIE;
GLLGAIAGFIE;
GLFAAIAGFIE;
GLFEAIAGFIE;
GLFGAMAGFIE;
GLFGAIAGLIE or the peptide
GLFGAIAGFIV
(Steinhauer et al., J. Virol, 69: 6643 (1995) hereby incorporated by reference)
or the peptide (SEQ ID NO:22)
GLFEAIAEFIEGGWEGLIEG
or the peptide (SEQ ID NO:23)
GLLEALAELLEGGWEGLLEG
(Ishiguro et al., Biochem., 32: 9792 (1993) hereby incorporated by reference).
Conjugation of the Ligands and Fusion Proteins to the Carrier
The ligands and fusion proteins are conjugated to the carrier using methods that are known to the skilled person.
Examples of Non-covalent Bonds
Choice of the Nucleotide Sequences for the Gene (d) which is to be Introduced
The nucleotide sequences that are to be complexed with the carrier can be DNA sequences or RNA sequences. In the simplest case, they comprise naked nucleotide strands that contain the gene that encodes the desired protein. This gene can be supplemented with cell-specific or virus-specific promoter sequences and, furthermore, with promoter modules.
Furthermore, viral promoter sequences and/or enhancer sequences can be added to the gene in order to amplify and/or extend expression of the gene. Promoter sequences and/or enhancer sequences of this nature are reviewed, for example, by Dillon, TiBTech, 11: 167 (1993) hereby incorporated by reference. Examples of promoter sequences and/or enhancer sequences of this nature are:
the LTR sequences of Rous sarcoma viruses
the LTR sequences of retroviruses
the promoter region and enhancer region of CMV viruses
the ITR sequences and/or the p5, p19 and p40 promoter sequences of AAV viruses
the ITR sequences and/or promoter sequences of adenoviruses
the ITR sequences and/or promoter sequences of vaccinia viruses
the ITR sequences and/or promoter sequences of herpesviruses
the promoter sequences of parvoviruses
the promoter sequences (upstream regulator region) of papilloma viruses
Preferably, the gene is incorporated into a plasmid.
Complexing the Conjugated Carriers (a) with the Gene (d)
The conjugated carrier is complexed with the gene, or the nucleotide sequence, by mixing the two starting substances. A mixing ratio should preferably be chosen which results in complexes which have a neutral or cationic charge.
Examples of preferred mixing ratios are:
1 xcexcmol of lipid/20 xcexcg of plasmid
1-5 mg of lipid/10-20 xcexcg of DNA/RNA
6.2 xcexcg of lipid/1.55-3.1 xcexcg of DNA
lipid/DNA-peptide (5:1)
The loading is effected by incubating the positively charged carrier with genes in the desired mixing ratio. The mixing ratio is determined (as described by Dittgen et al., Pharmazie, 42: 541 (1987) hereby incorporated by reference, by zeta potential measurement.